package com.java.main.io;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.springframework.http.MediaType;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.commons.CommonsMultipartFile;

import java.io.*;
import java.util.Base64;

/**
 * <p>
 *
 * </p>
 *
 * @author gzj
 * @since 2022/5/19
 */
public class IoUtil {

    public String inputstreamForBase64(ByteArrayInputStream byteArrayInputStream) throws IOException {
        ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
        byte[] buff = new byte[1024];
        int rc = 0;
        while ((rc = byteArrayInputStream.read(buff)) > 0) {
            swapStream.write(buff, 0, rc);
        }
        byte[] data = swapStream.toByteArray();

        return Base64.getEncoder().encodeToString(data);
    }

    /**
     * 获取封装得MultipartFile
     *
     * @param inputStream inputStream
     * @param fileName    fileName
     * @return MultipartFile
     */
    public MultipartFile getMultipartFile(InputStream inputStream, String fileName) {
        FileItem fileItem = createFileItem(inputStream, fileName);
        //CommonsMultipartFile是feign对multipartFile的封装，但是要FileItem类对象
        return new CommonsMultipartFile(fileItem);
    }


    /**
     * FileItem类对象创建
     *
     * @param inputStream inputStream
     * @param fileName    fileName
     * @return FileItem
     */
    public FileItem createFileItem(InputStream inputStream, String fileName) {
        FileItemFactory factory = new DiskFileItemFactory(16, null);
        String textFieldName = "multipartFile";
        FileItem item = factory.createItem(textFieldName, MediaType.MULTIPART_FORM_DATA_VALUE, true, fileName);
        int bytesRead = 0;
        byte[] buffer = new byte[8192];
        OutputStream os = null;
        //使用输出流输出输入流的字节
        try {
            os = item.getOutputStream();
            while ((bytesRead = inputStream.read(buffer, 0, 8192)) != -1) {
                os.write(buffer, 0, bytesRead);
            }
            inputStream.close();
        } catch (IOException e) {

            throw new IllegalArgumentException("文件上传失败");
        } finally {
            if (os != null) {
                try {
                    os.close();
                } catch (IOException e) {


                }
            }
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {

                }
            }
        }

        return item;
    }
}
